Abstract: Improvements in electronic apparatus connected with operation of ultrasonic thermometers consisting of an initiating electrical pulse generator which permits selection of the repetition rate at which the ultrasonic thermometer is to be operated, and, to avoid electrical interference caused by power switching, selective commencement of the initiating electrical pulse relative to the power line. Electronic amplifying and transmitting circuitry receiving the reflected information signal pulses from the ultrasonic thermometer amplify the pulses for transmission to pulse processing circuits remotely located from the furnace, assuring that sufficient signal amplitude is received by means of a returned automatic gain control signal to the amplifying and transmitting circuitry.

Abstract: An improved ultrasonic thermometer of the acoustic pulse-echo type for measuring high temperatures and temperature profiles having a magnetostrictive head surrounded by an acoustic pulse generating and pulse sensing apparatus having a positioned electromagnetic coil, the magnetostrictive head joined to an elongated heat sensing wire having a plurality of discontinuities at the distal end thereof to reflect a portion of the propagated acoustic pulse, the improvement comprising a lock fixedly holding the acoustic pulse generating and pulse sensing electromagnetic coil in alignment after initial adjustment in order to achieve long term stability.